The pensioner, who listened to his sentence at Stafford Crown Court via a prison videolink, pleaded guilty to the 20-year-old's murder at a previous hearing.

Eni, described by friends and fellow students at Staffordshire University as bright, intelligent and well-liked, suffered 16 separate wounds inflicted with a ten-inch blade.

Judge John Wait was told that Marshall was on licence at time of the murder in November last year, having served a three-year sentence for indecently assaulting a 14-year-old girl.

Eni, originally from Manchester, is believed to have met Marshall around six months before her death while she was out jogging.

Her killer, of Birks Street, Shelton, was told by Judge Wait that he is likely to die behind bars and will not be considered for parole until he is aged at least 88.

Handing Marshall a concurrent 30-month sentence for wounding a man who tried to halt the fatal attack, Judge Wait told the defendant: "It is clear from the number and position of the wounds that you had an intention to kill."

Eni was pronounced dead outside her shared property in Cauldon Road, Shelton, after Marshall fled from the scene despite attempts to lock him inside.

Marshall, who is being held at HMP Dovegate in Staffordshire, was under a duty to inform the authorities of any close relationships he formed with women, the court heard.

During his sentencing remarks, Judge Wait said Marshall had appeared to be jealous of Eni's other friendships.

Judge Wait told Marshall - who has 27 previous convictions from 17 separate court appearances: "At the time of this terrible offence you were on licence following a sentence for an offence of indecent assault.

"It was a condition of your licence that you notify your supervising (probation) officer of any developing friendship with a woman.

"It is noteworthy that you failed to tell your supervising officer of the relationship (with Eni) though you were asked on many occasions."

Marshall attacked Eni, who was sometimes overheard referring to him as "dad", at about 9.30pm on November 9 after letting himself into her home with a key.

Offering mitigation prior to sentence, defence barrister Patrick Thompson said his client could not recollect the "extremely wicked" killing or explain its motivation.

In a statement released after the case, Detective Inspector Andy Maxfield, of Staffordshire Police, said: "I want to reassure local residents and the student community that this was not a random attack.

"Eni and Marshall were known to each other.

"Through our detailed investigation we established that in the months prior to Eni's death she had struck up a friendship with Marshall.

"We welcome today's outcome and hope it brings some comfort to Eni's family."

Syed Shah, Eni's brother, also released a statement.

Mr Shah, aged 31, said: "Eni was a loving sister and daughter who was taken from us suddenly and violently.

"We are so proud of her achievements. She was beautiful, clever and had her whole life ahead of her. We are devastated by her death.

"Nothing can make up for that but we are glad Marshall is now paying for his actions."

Eni was in the second year of her studies for a degree in Policing and Criminal Investigation.

Speaking on behalf of Staffordshire University, Professor Andrew Jackson said: "Eni Mevish was a warm-hearted person and a conscientious, enthusiastic and capable student.

"She is greatly missed by all who knew her. Today's events bring that loss into sharp focus and our thoughts are particularly with her family at this very difficult time."